Glucose Biosensor Based on Immobilization of Glucose Oxidase in an Anionic Ion Exchange Polymer Blend

A fast and simple procedure to prepare a glucose oxidase electrode is presented herein. A blend of poly[(4-vinylpyridine)-co-styrene] and a polystyrene with quaternized amine groups, named PolyXIO, solubilized in methanol has been used for the immobilization of glucose oxidase at the surface of a platinum electrode. The response of the biosensor is saturated at 20 mM of glucose and a linearity of current versus glucose concentration is observed up to 4 mM. With 5U of GOD entrapped in the polymer membrane, the maximum current reached 200 A/cm2. The major advantages of this polymer blend lie in its good ionic diffusion capability, and because it has pendant groups opposite in charge to the outer groups on glucose oxidase.